The invention relates to an apparatus for comminuting organic substances, in particular for tearing apart fruits, including a plate supported rotatably about its axis along with a motor for driving it to rotate, with tearing elements disposed on one face end of the plate, and including means for delivering the organic substances to the face end of the plate.
A drum-type cutting machine, particularly for cutting sugar beets into pieces, is known from U.S. Pat. No. 4,584,919 (Bittner). It has a number of retaining elements that are disposed at equal spacings over the circumference of the drum and extend substantially parallel to the axis of the drum. A knife chest in which at least one cutting knife whose cutting edge extends substantially circumferentially is secured is retained between each two retaining elements.
Various embodiments of drum mills of this type are also known for tearing apart fruits, such as the types sold under the name Central by Bucher-Guyer AG, Niederweningen, Switzerland. A drum mill of this kind includes a drum body, made in one piece, over whose circumference retaining elements for the tearing knives are disposed at small spacings. In the operationally ready state, the drum of such a mill forms a substantially closed hollow chamber with a unilateral axial opening through which the fruits to be torn apart are delivered by means of a transporting screw.
In such drum mills, the following disadvantages have been demonstrated:
The fruits, especially apples, revolving at high speed in the drum create major imbalancing forces. The entire mill shakes and causes a great deal of noise. The imbalancing forces also adversely affect the service life of the bearings used for the drum.
Despite variation in terms of tooth pitch of the knives, the structure of the resultant mash can be varied only little. However, this structure influences the mash yield/performance in subsequent pressing operations, and this cannot be improved by optimizing the process.
Foreign bodies in the fruit product, such as stones, cause relatively major imbalance and cause severe damage to the tearing knives.
A fruit stuffing aid and the grinding drum operate at the same rotary speed. The mill fails to function at maximum capacity, since practically no prestuffing takes place. If too little fruit is delivered, the proportion of fine particles in the mash will be very high. This adversely affects the performance of an ensuing pressing operation and leads to clogging of filters for separating solids and liquids.
The casing of the grinding drum with the requisite mash outlet slots is very complicated to manufacture.
A plate-type cutting machine, particularly for cutting sugar beets into pieces, is also known from U.S. Pat. No. 4,683,790 (Bittner). This machine includes a machine stand and a plate cutter with a bearing and a drive mechanism. The plate cutter has a flat top and uniformly distributed openings for the cut-up product, which preferably extend a long way radially. Receptacles for cutting knives are disposed at the openings.
In plate-type cutting machines of the known type, the plate cutter usually comprises a steel plate with rectangular openings for the cut-up product. In such plate mills, the following disadvantages have been demonstrated:
Low capacity, since only part of the plate is acted upon.
A stuffing screw for delivering the product is either missing entirely or runs at the same rotary speed as the plate, leaving to an inadequate stuffing effect.
Excessively large thread pitches of the stuffing screw cause overload or blockage.
The function of the plate mill is only poorly adapted to the type of product to be ground.
The product of a cutting machine is unsuitable as pressing product for juice extraction.
The object of the invention is to overcome the disadvantages of the known apparatuses for comminuting organic substances through a novel design.
According to the invention, this object is attained in an apparatus of the type defined at the outset in that the means for delivering the organic substances are embodied as a stuffing device with a drive motor, and that the stuffing capacity of the stuffing device and the comminution capacity of the rotatably supported plate are adjustable independently of one another.
The stuffing device preferably includes a feed screw whose axis is located substantially in an extension of the plate axis. Advantageously, the stuffing device delivers the organic substances substantially to the entire end face of the plate via a cylindrical housing, whose outlet is opposite the end face at a spacing distance, and the cylindrical housing includes guide elements which block a rotary motion of the delivered organic substances. The tearing elements, disposed on the face end of the plate, are embodied as a plurality of interchangeably secured, substantially radially-extending tearing strips with sawlike edges, and on the face end of the plate, directly next to the radially-extending tearing strips, at least on one side thereof, there is a groove with an open end on the outer edge of the plate for carrying the comminuted organic substances away.
Advantageous operation of the apparatus is made possible by sensor means for detecting the operative torque in the rotational drive of the rotatably supported plate, as well as control means, operatively connected to the sensor means, for adjusting the stuffing capacity of the stuffing device to a value that corresponds to a predetermined value of this torque.
Further variants of the apparatus are defined by the claims.